boosting question on 335i

shock2314 · 03-11-2010, 06:52 PM

i'm a little new to the twin turbo motor and i have a question.
yesterday i got my boost gauge hooked up and while driving back i noticed that first and second gear boost was low between 5-8 lbs, once im in 3rd and 4th gear it goes up to 13-14 lbs. all i have as of right now is the giac flash stage 1. since i didnt have a boost gauge before i never really notice is that behavior was pre giac flash.
on my sr20det powered nissan altima my boost is constant in all gears (19 lbs) and im running a jim wolf tech stage 3 ecu program

so my question is.... is this normal?? dont want to sound like a noob but this has been bugging me since yesterday.

scalbert · 03-11-2010, 07:29 PM

Is this WOT and what rev range?

shock2314 · 03-11-2010, 07:58 PM

whats WOT?
and the rpm range was between 2k-6k. was pushing it to see what was my boost range

mkato13 · 03-11-2010, 08:07 PM

WOT is wide open throttle. Its normal to have low numbers in 1st and second gear. Winds up to fast to build high boost numbers. I dont know about your specific numbers but I hear that stock boost around 7-8 depending on temp and gear range. In my VW runnign stage 2 software I could see 13-15 psi in 1st gear and higher in each gear after. 18-19 in 2nd and 3rd and 21-22 in 4th-6th

scalbert · 03-12-2010, 08:48 AM

As mentioned, WOT = Wide Open Throttle.

In the lower gears, the engine can "out run" the turbo(s) and may see lower boost. But you also have to look at the conditions as well.

BaMBaM4002 · 03-12-2010, 11:34 AM

Quote:

Originally Posted by shock2314

whats WOT?

Who did your SR20 swap? Not you im assuming...

shock2314 · 03-12-2010, 02:11 PM

Quote:

Originally Posted by BaMBaM4002

Who did your SR20 swap? Not you im assuming...

trolling around ftw

cotmfk · 03-13-2010, 07:51 AM

Stock boos is 8 ish. I am not sure what the GIAC tune is like. Maybe it is tuned for lower boost in the lower gears for better traction?

03-11-2010, 06:52 PM	#1
shock2314 Lieutenant 54 Rep 518 Posts Drives: Brooklyn G80 m3 Join Date: Oct 2009 Location: DMV iTrader: (0)	boosting question on 335i i'm a little new to the twin turbo motor and i have a question. yesterday i got my boost gauge hooked up and while driving back i noticed that first and second gear boost was low between 5-8 lbs, once im in 3rd and 4th gear it goes up to 13-14 lbs. all i have as of right now is the giac flash stage 1. since i didnt have a boost gauge before i never really notice is that behavior was pre giac flash. on my sr20det powered nissan altima my boost is constant in all gears (19 lbs) and im running a jim wolf tech stage 3 ecu program so my question is.... is this normal?? dont want to sound like a noob but this has been bugging me since yesterday. __________________ RIP E46 M3 RIP E92 335i RIP F80 M3 Hello G80 M3
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03-11-2010, 07:29 PM	#2
scalbert Major General 161 Rep 5,776 Posts Drives: '13 S4, '15 Q7 Join Date: Feb 2007 Location: Woodstock, GA iTrader: (8)	Is this WOT and what rev range?
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03-11-2010, 07:58 PM	#3
shock2314 Lieutenant 54 Rep 518 Posts Drives: Brooklyn G80 m3 Join Date: Oct 2009 Location: DMV iTrader: (0)	whats WOT? and the rpm range was between 2k-6k. was pushing it to see what was my boost range __________________ RIP E46 M3 RIP E92 335i RIP F80 M3 Hello G80 M3
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03-11-2010, 08:07 PM	#4
mkato13 Second Lieutenant 8 Rep 278 Posts Drives: 2010 Jet Black 335xi Join Date: Dec 2009 Location: Northern NJ iTrader: (0)	WOT is wide open throttle. Its normal to have low numbers in 1st and second gear. Winds up to fast to build high boost numbers. I dont know about your specific numbers but I hear that stock boost around 7-8 depending on temp and gear range. In my VW runnign stage 2 software I could see 13-15 psi in 1st gear and higher in each gear after. 18-19 in 2nd and 3rd and 21-22 in 4th-6th
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03-12-2010, 08:48 AM	#5
scalbert Major General 161 Rep 5,776 Posts Drives: '13 S4, '15 Q7 Join Date: Feb 2007 Location: Woodstock, GA iTrader: (8)	As mentioned, WOT = Wide Open Throttle. In the lower gears, the engine can "out run" the turbo(s) and may see lower boost. But you also have to look at the conditions as well.
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03-13-2010, 07:51 AM	#8
cotmfk Major General 2133 Rep 6,195 Posts Drives: M3 Join Date: Mar 2009 Location: FL iTrader: (12)	Stock boos is 8 ish. I am not sure what the GIAC tune is like. Maybe it is tuned for lower boost in the lower gears for better traction? __________________ T1M3LESS M3 is for sale https://f80.bimmerpost.com/forums/sh....php?t=1423045
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